METHOD AND STRUCTURE FOR COAXIAL VIA ROUTING IN PRINTED CIRCUIT BOARDS FOR IMPROVED SIGNAL INTEGRITY

摘要

A method and a structure for a coaxial via that extend along the entire length of a signal via in a printed circuit board. Signal integrity is improved by providing ground shield for the entire length of the coaxial via. The ground shielding can be implemented by either providing ground cage vias around a signal via and routing a trace to the signal via on a built up layer or by providing a semi circle ground trench through a build up layer to permit a trace access to the signal via.